Pressure sensor unit, especially for automotive engineering applications

ABSTRACT

A pressure sensor suitable for use in automotive applications is provided to sense the pressure of a pressurized fluid medium and generate an electrical signal representative of the sensed pressure on a set of electrical contact members. A main housing body has a fluid supply opening adapted to conduct a pressurized fluid medium into the housing body. A pressure measuring cell is provided including a plastic measuring cell housing and an electric pressure sensor arranged on the plastic measuring cell housing. The pressure measuring cell is disposed on the housing body of the pressure sensor apparatus adjacent the fluid supply opening so that at least part of the electric pressure sensor is acted upon by the pressurized fluid medium. A reinforcement plate member is adapted to engage a back side of the pressure measuring cell to hold the pressure measuring cell in place relative to the main housing body against the pressure of the pressurized fluid medium. At least two electrical conductors are integrally molded into the plastic measuring cell housing and extend completely through the plastic measuring cell housing and through the reinforcement plate member to form first and second sets of electrical contacts on opposite high and low pressure sides of the plastic measuring cell housing to enable electrical connection to the electric pressure sensor disposed in the main housing body.

BACKGROUND OF THE INVENTION

The subject invention is directed to the pressure sensor arts and, moreparticularly, to pressure sensor apparatus suited for use in automotiveapplications to sense the pressure of a pressurized fluid medium andgenerate electrical signals representative of the sensed pressure.

Pressure sensors of the type under consideration are well known in theautomotive engineering community. A multiplicity of designs have beenused in automotive applications such as, for example, as sensor elementsfor monitoring the oil pressure of an engine or to monitor brakepressure, or the like.

Generally, pressure sensor units typically comprise a housing having aninlet opening adapted to receive a small quantity of the pressurizedfluid medium intended to be monitored. Typically, the pressurized fluidmedium is conducted into the housing via the inlet opening towards apressure measuring cell located within the housing. Many pressure sensorhousings are provided with external threading so that the housing can bescrewed into place on an engine block or brake cylinder havingcorresponding intermateable threads.

On important consideration in pressure sensors used for automotiveapplications is their long-term stability and resistance to aggressivemedia as well as survivability in rough environmental conditions. Oneproposed solution to protect the pressure sensors from aggressive fluidsthat may cause damage has been to provide a barrier between the pressuresensor and the fluid. Sensors of this type are known in the art as“media-separated” pressure sensor units. There, the monitoredpressurized fluid medium does not come into actual direct contact withthe sensor element itself but, rather, acts indirectly upon the pressuresensing device through an intermediary separation membrane. In thesedesigns, the sensitive sensor element disposed within the housing istypically arranged in a measuring cell housing which is in turnprotected from aggressive fluid medium by means of the above-notedseparation membrane. An interstitial pressure transfer medium is oftenused to transfer the pressure generated by the fluid medium to bemonitored to the sensor element. Normally, the pressure transfer mediumoccupies the void between the separation membrane and the sensor elementproper. Pressure sensor units of this type are well known in the art andare described in the literature including German Patent DE 295 11 996U1.

One disadvantage of media-separated pressure sensor units, however, isthat it is often difficult and costly to install the pressure measuringcell into the housing. Typically, the pressure measuring cell comprisesone or more housing components and a fragile sensor element arrangedtherein. Major contributors to the difficulty and expense in fabricatingthe media-separated pressure sensor units include the step of installingthe pressure sensor element on one or more appropriate support elementsand further, the step of establishing electrical and mechanicalconnections to the sensor element.

Inasmuch as all sensor elements must be positioned in a manner to enablethe measured fluid to act upon the sensor element, it is necessary toroute the electrical pressure sensor connectors on a side of the supportelement facing away from the pressurized fluid medium. Typically, theelectrical connections are not routed toward the pressurized medium.Normally also, in order to absorb and transfer the high pressure forcesgenerated by the pressurized fluid medium to the housing, the supportelements are usually formed of metal. Accordingly, routing theelectrical connections on a side of the support element facing away fromthe pressurized fluid medium is difficult. It is well known that metalsupport elements conduct electricity. Therefore, in pressure sensorsthat use metal support elements, it is necessary to extend the sensorelectrical connection contacts in an isolated fashion through the metalsupport element on a side opposite the pressurized fluid medium. Anexample is shown in DE 295 11 976 U1. The complexity of the electricalconnections in pressure sensors of this type is commensurate with theexpense thereof.

A alternative pressure sensor is described in German patent applicationDE 196 37 763 wherein a pressure sensor unit includes a measuring cellhaving a measuring cell housing retained in the main housing of thepressure sensor unit. In that example, the measuring cell housing isprovided with a central breakout portion whereat a pressure sensorelement is installed from a rear side of the breakout portion. Thepressure sensor element is located in a TO-type housing. The TO-typehousing is tightly joined with the measuring cell by means of welding.It is an advantage of the above-described construction that the sensorelement proper can be pre-installed in the measuring cell housing andjoined thereto before the pressure sensor unit itself is constructed. Incontrast to prior known sensor units, this results in the benefit of aless complicated installation. One expense that remains, however, is aresult of the need to install the sensor element proper into the TO-typehousing. Further, an additional expense drawback is the requirement forthe firm and tight joining of the TO-type housing to the measuring cellhousing.

It is desirable, therefore, to provide a pressure sensor that is able towithstand aggressive fluid media and rough environmental conditionswhile being simple and relatively inexpensive to construct.

SUMMARY OF THE INVENTION

The subject invention provides a pressure sensor apparatus that isparticularly well suited for use in automotive applications and whichcan be manufactured with little expense and is thus cost-effective. Thepressure sensor apparatus of the invention is adapted to sense thepressure of a pressurized fluid medium and generate an electrical signalrepresentative of the sensed pressure on a set of electrical contactmembers. A housing member is provided including a fluid supply openingadapted to conduct a pressurized fluid medium into the housing member. Apressure measuring cell includes a plastic measuring cell housing and anelectric pressure sensor arranged on the plastic measuring cell housing.The pressure measuring cell is disposed in the housing body adjacent thefluid supply opening so that at least a part of the electric pressuresensor is acted upon by the pressurized fluid medium. A reinforcementplate member adapted to engage a first side of the pressure measuringcell holds the pressure measuring cell in place relative to the housingbody against the pressure of the pressurized fluid medium. At least twoelectrical conductors are molded integrally with and into the plasticmeasuring cell housing. The at least two electrical conductors extendcompletely through the plastic measuring cell housing and through thereinforcement plate member to form a first and second set of electricalcontacts. The first set of electrical contacts are adjacent the firstside of the plastic measuring cell and are operatively connected to theset of electrical contact members provided on the pressure sensorapparatus. The second set of electrical contacts are disposed upon asecond side of a plastic measuring cell housing opposite the first sideand are operatively connected to the electric pressure sensor.

It is an advantage of the present invention that by injection-molding ofthe at least two electrical conductors integrally with and directly intothe measuring cell housing, the costs associated with manufacturing themeasuring cell or the pressure sensor unit overall is significantlyreduced.

The sensor element proper, which is preferably formed on a semiconductorchip, is arranged directly on or in the measuring cell housing. Theelectrical connections to the pressure sensor are connected by bondingwith electrical contact terminals which project from the side of themeasuring cell housing which is acted upon by the pressurized fluidmedium or the pressure transfer medium. In this fashion, the subjectmeasuring cell can be produced in a simple manner and, further, isadapted to be easily and simply installed within the housing body of thepressure sensor unit. In a preferred embodiment of the invention, theelectrical conductors are fashioned in the form of a punched-out grid orstamped parts, which is/are bent to the desired shaped prior to orduring the extrusion molding process. Preferably, the punched-out gridelectrical conductor is formed in such a manner that the respectivecontact terminals are connectable by means of bonding with correspondingcontacts on the pressure sensor proper. In order to ensure good bonding,it is required that the connection contact terminals of the punched-outgrids, or stamped leads, are polished or, at a minimum, include polishedregions. Furthermore, during the entire manufacturing process of moldingthe pressure measuring cell, care must be taken that the bonding regionsof the punched-out grids not become dirty. As a specific example, it ispreferred that no separation medium is employed during the extrusionprocess. Therefore, in fabricating the pressure measuring cell of theinstant application, it is preferred that steeper slopes be used ordesigned into the shape in order to facilitate the formation of theextruded pressure measuring cell component.

It is a further advantage of the present invention that the contactterminals of the electrical conductors which protrude from the side ofthe measuring cell housing facing away from the pressurized fluid mediumsimultaneously serve as mechanical mounting supports for electricalcircuits such as, for example, electronic circuits that evaluate,analyze, or process the sensor signals. More particularly, the contactterminals on the side opposite the pressurized fluid medium are formed,in accordance with the present invention, to engage a corresponding setof connectors that form part of an electronic circuit or otherelectronic wiring within the housing body of the pressure sensor. Thecontact with the sensor terminals for electronic wiring or electroniccircuits can be made in many ways but, preferably, includeelement-conforming inserts or cutting-type contacts which respectivelycooperate with each other. More particularly, as a preferred example,insert or cutting-type contacts are provided at the electronic wiring orelectronic circuit portion for electrical and mechanical engagement witha corresponding intermateable element conforming-type contacts at thepressure measuring cell.

It is a further advantage of the preferred embodiment of the inventionthat the pressure sensor comprises an integrated circuit chip which isglued onto an interior wall of a recess formed in the measuring cellhousing. This results in an extremely simple construction of thepressure measuring cell. In accordance with another specific embodimentof the invention, for example, in order to produce extremelytemperature-stable pressure sensor units, the pressure sensor isdisposed on the surface of a rigid element provided at or inside themeasuring cell housing. Preferably, the rigid element is made of aceramic material. As a result, any tensions that may exist or formduring manufacture or use within the measuring cell housing such asthose produced by changes in the temperature, are not transmitted to thesensitive sensor element proper. Thus, measuring errors and destructionof the sensor element proper, are safely avoided.

In accordance with another advantage of the invention, a reinforcementplate is provided on the backside of the measuring cell housing. Thereinforcement plate is preferably used when highly pressurized fluidmedium is to be measured. The reinforcement plate preferably includesperforations for allowing the connection contacts to pass therethroughin a manner to be subsequently described. In addition, the reinforcementplate is alternatively injection molded into the measuring cell housingor extruded into same.

Still other advantages and benefits of the invention will becomeapparent to those skilled in the art upon a reading and understanding ofthe following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangementsof parts, the preferred embodiments of which will be described in detailin this specification and illustrated in the accompanying drawings whichform a part hereof, and wherein:

FIG. 1 is a cross-sectional view showing the overall arrangement of ahigh pressure sensor apparatus formed in accordance with the firstpreferred embodiment of the invention;

FIG. 2 is a perspective view of a lower housing portion of a medium andlow pressure sensor apparatus in partial cross-section formed inaccordance with a second preferred embodiment of the invention; and,

FIG. 3 is a cross-sectional view showing the overall arrangement of alow to medium pressure sensor apparatus formed in accordance with athird preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings wherein the showings are for the purposesof illustrating the preferred embodiments of the invention only and notfor purposes of limiting same, the overall arrangement of the firstpreferred form of a pressure sensor apparatus formed in accordance withthe invention can best be seen by reference to FIG. 1. As shown therein,the pressure sensor unit 1 consists of a two-piece main housing body 3within which is disposed a pressure measuring cell 5. The housing body 3is preferably formed of metal or high-strength plastic for reasons thatwill subsequently become apparent.

Generally, the pressure measuring cell 5 is mounted in the lower, firsthousing component 3 a of the housing body as shown. A recess 7 isprovided in the housing body for receiving the pressure measuring cell 5and is preferably shaped in the form of a bore hole which has, in itslower portion, an inner diameter that essentially corresponds to theouter diameter of a measuring cell housing 9. Preferably, the measuringcell housing is disc-shaped although other suitable forms and shapes canbe used.

A substantially circular-cylindrical extension 11 is formed on the lowerregion of the first housing component 3 a and includes a threaded region13 as shown. In that way, the pressure sensor unit 1 can be threadedinto a corresponding threaded bore hole such as, for example, into acylinder of an internal combustion system or engine block. A supplyopening 15 enables the communication of a pressurized fluid medium intothe housing body 3 through the extension or prolongation 11. In thatway, the pressurized fluid medium is delivered and brought into contactwith the pressure measuring cell 5 to act on the pressure measuringcell. As shown in the figure, the pressure measuring cell 5 is disposedwithin the housing body 3 adjacent the fluid supply opening 15 so thatat least a part of an electric pressure sensor 19 is acted upon by thepressurized fluid medium that is communicated through the supplyopening. The measuring cell housing 9 includes a central recess 17 thatis adapted to receive the electric pressure sensor 19 as shown. Althoughthe electric pressure sensor 19 can be formed in many ways, a preferredexample includes a silicone membrane with integrated piezo-resistivesemi-conductor resistors.

In accordance with the present invention, the measuring cell housing 9is an injection-molded plastic component. Further in accordance with theinvention, at least two electrical conductors 21 are molded directlyinto the plastic measuring cell housing 9 and are thereby formedintegrally therewith. This results in the benefit that the electricalconductors 21 form a hermetically tight and electrically isolated sealthrough the measuring cell housing 9 on the side of the measuring cellhousing facing away from, or opposite from, the pressure side adjacentthe supply opening 15.

In accordance with the invention, the at least two electrical conductorsare preferably formed as bent punched-out grids or bent stamped parts.As shown in the figure, the electrical conductors 21 are preferablyfashioned on their respective upper ends as cutting contacts that extendfrom the measuring cell housing in an orientation so as to interactdirectly with terminal lugs 23 associated with an electronic wiring 25.The electronic wiring 25 is represented in the preferred embodiment asbeing disposed in the upper, second housing component 3 b of housingbody 3. To that end, a plate portion 25 a of an electronic circuit 25 isequipped with lateral recesses that are adapted to engage acorresponding set of grip retainer arms 23 which are joined to the upperhousing component 3 b of the housing body 3. With the aboveconstruction, the electrical connection between the terminal lugs 23 ofthe electronic circuit 25 and the respective contact ends of theelectrical conductors or punched-out grids 21 is accomplished simply byinserting the upper housing member 3 b into the lower housing member 3a.

For the above purpose, the lower housing component 3 a is provided witha coupling region 29 with a shoulder that acts as a stop for the frontside of the upper housing component 3 b. An upper housing wall 31 isadapted to be bent over into engagement with a shoulder region 33 formedon the underside of the upper housing component 3 b. The upper housingwall 31 can be crimped or otherwise bent into the position shown in FIG.1 subsequent to intermateable engagement between the upper and lowerhousing members 3 b, 3 a. In that way, after pushing together the twohousing components 3 a, 3 b a firm connection is formed therebetween.

With continued reference to FIG. 1, the upper housing component 3 b isprovided with an insertion connection zone including exterior connectioncontacts 35. The exterior electrical contacts 35 enable the subjectpressure sensor unit 1 to be connected to an associated electric circuit(not shown) via a suitably configured insertion plug (not shown).Preferably, the connection contacts 35 are connected by means ofelectrical connection lines 37 with the electronic circuit 25 disposedin the upper housing component 3 b. Alternatively, intermateableinsertion-plug type connections can also be employed in order toestablish electrical contact between the exterior connection contacts 35and the electronic wiring 25.

In the first preferred embodiment of the invention shown in FIG. 1, themeasuring cell housing 9 includes a reinforcement element 39 adapted toengage a first side of the pressure measuring cell 5 and hold thepressure measuring cell in place relative to the housing body 3 againstthe pressure of the pressurized fluid medium contained in the supplyopening 15. As shown, the reinforcement element 39 is disposed on theposterior side facing away from the pressurized fluid medium.Preferably, the reinforcement element 39 comprises a metal plate whichincludes a pair of perforations 41 through which pass the contact endsof the electrical conductors or of the punched-out grids 21. Inaccordance with the invention, the reinforcement element 39 issuperposed as a loose disc onto the plastic extrusion component of themeasuring cell housing 9 during installation of the pressure sensorunit. Alternatively, it is extruded into the plastic injection moldedpiece. Still further yet, it is alternatively injection molded into themeasuring cell housing.

Turning now to the fabrication of the subject pressure sensor apparatus,the pressure measuring cell 5 is installed within the housing body 3 byfirst filling the recess 17 with a pressure transmission medium 42 sincethe exemplary embodiment represented in FIG. 1 involves amedia-separated pressure sensor unit. After the recess 17 is filled withthe pressure transmission medium 42, the measuring cell housing 9 isinserted together with a separation membrane 43 into the recess 7 of thelower housing component 3 a. A sealing ring 45 is disposed in acircumferential groove so that, by pressing the measuring cell housing 9against the bottom side of the recess 7, a tight seal is formed so thatthe pressure transmission medium 42 is unable to escape from the spaceformed by the recess 17 and the separation membrane 43.

As represented in FIG. 1, the measuring cell is fastened into place inthe position shown by means of a peeling process of one or more regionsor a continuous circumferential region of the lateral interior wall ofthe recess 17. Preferably, the one or more regions are peeled and bentinwardly to grab behind the measuring cell housing. In this way, it ispossible through the installation process to generate a correspondingpressure on the measuring cell housing 9 so that the measuring cellhousing is essentially retained in place subsequent to the peelingprocess. Alternatively, rather than using a peeling process, themeasuring cell housing 9 can also be fastened by tapering the housingcomponent 3 a which is preferably made of metal. To that end, the lowerhousing component 3 a could alternatively be radially squeezed above theupper end of the inserted measuring cell housing thereby holding themeasuring cell housing in place as the outer walls of the lower housingcomponent 3 a are swaged inwardly.

As is apparent from FIG. 1, the pressure sensor 19 is disposed on theinterior wall of the groove 17 in the measuring cell housing 9 using ade-coupling element 47 which, preferably, is formed from a small ceramicplate. The small ceramic de-coupling element 47 is preferably glued ontothe interior side of the recess 17. Alternatively, the ceramic plate 47is injected molded together with the plastic injection molding componentof the measuring cell housing 9. By using the de-coupling element,transmission of tensions, stresses, and strains to the sensitive sensor19 is prevented. The tensions may be caused, for example, by changes intemperature or may occur during the installation process of themeasuring cell housing 9 into the housing body 3. For certainapplications, the de-coupling element 47 need not be used. As anexample, the de-coupling element may be waived through utilization ofappropriate plastics or mixed materials in the measuring cell 9.

From the above, it is apparent that the pressure sensor shown in FIG. 1is specifically adapted for measuring high pressures. However, theexemplary embodiment presented in FIG. 2 is more particularly adaptedfor use with lower and medium pressure fluid mediums.

Turning now to FIG. 2, only the lower housing component 3 a of thehousing body 3 is shown in a partially sectioned perspective view. Asshown there, a measuring cell 5 is installed on the bottom of the recess7 of the lower housing component 3 a. The measuring cell 5 basicallycorresponds to the measuring cell depicted in connection with FIG. 1.With respect to the embodiment shown in FIG. 2, however, thereinforcement plate 39 described above in connection with FIG. 1 neednot be used because, as indicated above, the device shown in FIG. 2 isadapted for low and medium pressure monitoring.

Preferably, the measuring cell housing 9 consists of a plastic extrusioncomponent into which are extruded electrical conductors 21. In thespecific embodiment shown in FIG. 2, the electrical conductors 21 areshaped as punched-out grids and, as such, are designed in a manner thatthey emerge on the pressure-distal side of the measuring cell housing 9in such a fashion that the measuring cell housing 9 simultaneouslyfunctions as an electrical conductor plate. An advantage of the designof the electrical conductors 21 shown in FIG. 2 is that it is possibleto weld electronic building components, such as, for example, integratedcircuits, particularly ASICs, directly onto the electrical conductors21. As shown in the figure, a surface-mounted integrated circuit iswelded onto the electrical conductors.

Contacting of the electronic building components of the outer connectioncontacts arranged in the upper housing component (not shown) is enabledby means of contact connection terminals 21 a which extend verticallyfrom the measuring cell housing 9 in the direction of the upper housingcomponent. In order to make contact with the terminals 21 a, acorresponding set of counter-contacts are preferably formed in the upperhousing component and oriented in a downward direction. It is to benoted, however, that the arrangement of the electronic circuits, theelectronic wiring, contacting of the sensor 19, or of the outerconnection contacts 35 discussed above in connection with the embodimentshown in FIG. 1, can also be used as needed or desired in the embodimentrepresented in FIG. 2.

Turning lastly to FIG. 3, a third preferred embodiment of the subjectinvention is illustrated in cross-section. This embodiment is preferablysuitable for use with low and medium pressure fluids where the pressuremeasuring cell housing 9 is acted upon by a radially inwardly extendingshoulder 50 of the upper housing component 3 b. The two housingcomponents 3 a, 3 b are connected simply by crimping a wall member 31 ofthe lower housing component 3 a inwardly after the two housingcomponents 3 a, 3 b are brought into contact. The measuring cell 5 isfastened within the housing after the two housing components are broughtinto contact and the crimping wall 31 is bent over. This simpleprocedure enables a reduced manufacturing and assembly cost to thesubject pressure sensor apparatus. The entire required electronics canbe integrated into the sensor 19 or, signal evaluation can take placeoutside the sensor unit. The conductors 21 extruded into the measuringcell housing 9 can therefore be designated in a single piece withconnection contacts 35 or the ends of conductors 25 can exit from thesurface of the measuring cell housing 9 as connection contacts 35. Tothus form the conductors 21 integral with the connection contacts 35results in a further reduction of the manufacturing and assembly costs.

Still further, if additional electrical or electronic buildingcomponents are needed, the connection contacts 35 can also be extrudedinto the measuring cell housing 9 and serve, concurrently, the same asconductors 21, as mechanical supports for building elements.

In addition to the above, the upper housing component 3 b can also beformed as a single piece with measuring cell housing 9, so that forassembly of the sensor unit only two parts need to be installed, notcounting the pressure sensor 19. Therefore, as a result of theutilization of a plastic extrusion component, at least as an essentialelement of the measuring cell housing 9, into which electrical contactsfor establishing contact with the pressure sensor 19, a definitesimplification is achieved with respect to the manufacture of thepressure measuring cell, as well as its installation into the housingbody of the pressure sensor unit.

The invention has been described with reference to the preferredembodiments. Obviously, modifications and alterations will occur toothers upon a reading and understanding of this specification. It isintended to include all such modifications and alterations insofar asthey come within the scope of the appended claims or the equivalentsthereof.

What is claimed is:
 1. A pressure sensor unit comprising: a housing inwhich is arranged a pressure measuring cell, a supply opening fordirecting a pressure medium, and exterior connection contacts leadingfrom the interior of the housing toward the outside, the pressuremeasuring cell including a measuring cell housing in which is arranged apressure sensor which is acted upon by a pressure medium; the electricalcontacts of the pressure sensor being connected with a one of theexterior connection contacts and the connections of an electroniccircuit; the measuring cell housing including a plastic extrusioncomponent into which have been injected at least two electricalconductors, whereby the electrical conductors respectively protrude withat least one first contact end into a region for acceptance of thepressure sensor and are respectively connected with an electricalconnection of the pressure sensor; the electrical conductors protrudingwith respectively at least one second contact end into a region of themeasuring cell housing not acted upon by the pressure medium and whichis connected with the exterior connection contacts or the connections ofthe electronic circuit, and a reinforcement plate, fastened in housingsupporting a back side of said measuring cell housing.
 2. A pressuresensor apparatus to sense the pressure of a pressurized fluid medium andgenerate an electrical signal representative of the sensed pressure on aset of electrical contact members, the pressure sensor apparatuscomprising: a housing body including a fluid supply opening adapted toconduct a pressurized fluid medium into the housing body; a pressuremeasuring cell including a plastic measuring cell housing and anelectric pressure sensor arranged on the plastic measuring cell housing,the pressure measuring cell being disposed on the housing body adjacentthe fluid supply opening so that at least part of the electric pressuresensor is acted upon by said pressurized fluid medium; a reinforcementplate member adapted to engage a first side of the pressure measuringcell and hold the pressure measuring cell in place relative to thehousing body against said pressure of the pressurized fluid medium; and,at least two electrical conductors molded into the plastic measuringcell housing, the at least two electrical conductors extendingcompletely through the plastic measuring cell housing and through saidreinforcement plate member to form, adjacent to said first side of theplastic measuring cell, a first set of electrical contacts operativelyconnected to said set of electrical contact members and to form, on asecond side of the plastic measuring cell housing opposite said firstside, a second set of electrical contacts operatively connected to saidelectric pressure sensor.
 3. The pressure sensor apparatus according toclaim 2 wherein said at least two electrical conductors comprise punchedout grids.
 4. The pressure sensor apparatus according to claim 3 whereinsaid electric pressure sensor includes a semi-conductor chip.
 5. Thepressure sensor apparatus according to claim 4 wherein saidsemi-conductor chip includes electronics adapted to perform processingand evaluation.
 6. The pressure sensor apparatus according to claim 2wherein said second set of electrical contacts formed by the at leasttwo electrical conductors are bonded to said electric pressure sensor.7. The pressure sensor apparatus according to claim 2 wherein saidsecond set of electrical contacts formed by the at least two electricalconductors are adapted to mechanically support an associated electroniccircuit within said housing body.
 8. The pressure sensor apparatusaccording to claim 7 wherein: said associated electronic circuitincludes a connector member; and, said second set of electrical contactsformed by the at least two electrical conductors include an insertionend adapted to engage the connector member of the associated electroniccircuit.
 9. The pressure sensor apparatus according to claim 2 whereinsaid electric pressure sensor is glued directly onto a wall of saidplastic measuring cell housing.
 10. The pressure sensor apparatusaccording to claim 2 further comprising a decoupling member disposedbetween the electric pressure sensor and said plastic measuring cellhousing.
 11. The pressure sensor apparatus according to claim 10 whereinsaid decoupling member is molded into the plastic measuring cellhousing.
 12. The pressure sensor apparatus according to claim 2 whereinsaid reinforcement plate member is molded into the plastic measuringcell housing.
 13. A pressure measuring cell for use in a pressure sensorapparatus to sense the pressure of a pressurized fluid medium andgenerate an electrical signal representative of the sensed pressure on aset of electrical contact members arranged on a main a housing body ofthe pressure sensor apparatus, the main a housing body including a fluidsupply opening adapted to conduct a pressurized fluid medium into thehousing body, the pressure measuring cell comprising: a plasticmeasuring cell housing; an electric pressure sensor arranged on theplastic measuring cell housing, the pressure measuring cell beingdisposed on the housing body adjacent the fluid supply opening so thatat least part of the electric pressure sensor is acted upon by saidpressurized fluid medium; a reinforcement plate member adapted to engagea first side of the pressure measuring cell and hold the pressuremeasuring cell in place relative to the housing body against saidpressure of the pressurized fluid medium; and, at least two electricalconductors molded into the plastic measuring cell housing, the at leasttwo electrical conductors extending completely through the plasticmeasuring cell housing and through said reinforcement plate member toform, adjacent to said first side of the plastic measuring cell, a firstset of electrical contacts operatively connected to said set ofelectrical contact members and to form, on a second side of the plasticmeasuring cell housing opposite said first side, a second set ofelectrical contacts operatively connected to said electric pressuresensor.
 14. The pressure measuring cell according to claim 13 whereinsaid at least two electrical conductors comprise punched out grids. 15.The pressure measuring cell according to claim 14 wherein said electricpressure sensor includes a semi-conductor chip.
 16. The pressuremeasuring cell according to claim 13 wherein said electric pressuresensor is glued directly onto a wall of said plastic measuring cellhousing.
 17. The pressure measuring cell according to claim 13 furthercomprising a decoupling member disposed between the electric pressuresensor and said plastic measuring cell housing.
 18. The pressuremeasuring cell according to claim 17 wherein said decoupling member ismolded into the plastic measuring cell housing.
 19. The pressuremeasuring cell according to claim 13 wherein said reinforcement platemember is molded into the plastic measuring cell housing.